I also agree. If you express this opinion on the IMDb you are told that you are an "Ashton Hater" or a "Charlie Fanboy".
I'm neither. Although, looking back on old episodes, I can see that Charlie gave the show a certain charm that's hard to decribe. Charlie Harper was a womaniser, a cheat, an alcoholic but, especially in the earlier seasons, his heart seemed to be in the right place. Or else his charisma made it easier to overlook his many, many flaws.
Ashton I don't hate. I do however think that the character of Walden is lacking. The show is threading water at the moment, none of the old characters are developing. Jake is just getting more stupid, Alan's meaness was cringeworthy enough when he was sponging off his brother, to do the same to a stranger is not only reprehensible but also wholly unbelievable. If Walden is that lonely he could move a friend in. He doesn't owe Alan anything. All Alan ever did for him is allow him into the house to make a phonecall and tell his ex-wife that the woman Walden was standing beside was actually his date. (A trick he learned from Charlie.)
Berta fawning over Walden is a one-trick pony that every female in the show seems to ride, Evelyn and Judith are rarely in the show and Rose is completely gone.
Classic Two And A Half Men wasn't the greatest show ever (imho) but it was a helluva lot better than the current run.